system-arm: change system/arm/aarch64_bootloader/boot.S copyright
The aarch64 boot loader was distributed using a BSD license that was
using non-standard formatting. Updated the license to match gem5's
canonical license format and removed the separete LICENSE.txt file.
Change-Id: I660b73ca5ddd922763a2b72051c73d539248ebcf
Reviewed-by: Andreas Sandberg <andreas.sandberg@arm.com>
Signed-off-by: Andreas Sandberg <andreas.sandberg@arm.com>
Reviewed-on: https://gem5-review.googlesource.com/5728
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Jason Lowe-Power <jason@lowepower.com>